|Publication number||US7118830 B1|
|Application number||US 10/806,922|
|Publication date||Oct 10, 2006|
|Filing date||Mar 23, 2004|
|Priority date||Mar 23, 2004|
|Also published as||CN1957491A, CN1957491B, CN101944613A, EP1735860A2, EP1735860A4, US20060240325, WO2005094501A2, WO2005094501A3|
|Publication number||10806922, 806922, US 7118830 B1, US 7118830B1, US-B1-7118830, US7118830 B1, US7118830B1|
|Inventors||David Paul Boden, Benjamin Paul Labovitz|
|Original Assignee||Hammond Group, Inc.|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (71), Referenced by (10), Classifications (24), Legal Events (7)|
|External Links: USPTO, USPTO Assignment, Espacenet|
The present invention relates generally to battery pastes and the curing process for battery plates. In particular, an improvement to battery paste and the curing process for battery plates for lead acid batteries is disclosed. More specifically, the present invention comprises a battery paste additive of micronized tetra basic lead sulfate crystals used to promote formation of additional tetra basic lead sulfate in the paste and plates. As a result, the curing process is accelerated and the resultant positive and negative battery plates have improved performance characteristics.
Traditional methods for producing battery plates for lead-acid batteries generally involve a mixing, curing and drying operation in which the active materials in the battery paste undergo chemical and physical changes that are used to establish the chemical and physical structure and subsequent mechanical strength necessary to form the battery plate. To produce typical battery plates, materials are added to commercial paste mixing machines common in the industry in the order of lead oxide, flock, water and sulfuric acid, which are then mixed to a paste consistency. During mixing, chemical reactions take place in the paste producing basic lead sulfates, the most common of which is tribasic lead sulfate. The final paste composition is a mixture of basic lead sulfates, unreacted lead monoxide and residual free lead particles. Pasting is the process of making a battery plate from the paste mix. This paste is dispersed into a commercial automatic pasting machine of a type common in the industry which applies the paste to a grid structure composed of a lead alloy. The paste is dispensed into a hopper on the pasting machine and from there the paste is applied to the grids at high speed. The paste plates are generally surface dried in a tunnel dryer of a type common in the industry and then either stacked in columns or placed on racks. The stacked or racked plates are then placed in curing chambers. In these chambers the plates are subjected to temperatures of 70° C.–80° C. in a high humidity atmosphere to convert the tribasic lead sulfate in the plates to tetra basic lead sulfate and to allow oxidation of the residual free lead. The finished plates are now ready for assembly into batteries.
Two key factors important in the curing process are the formation of a proper crystal structure by converting tribasic lead sulfate (TRBLS) formed during paste mixing into tetra basic lead sulfate (TTBLS), and the formation of tetragonal lead oxide by oxidizing residual free lead metal. Generally, a crystal structure high in tetra basic lead sulfate will increase battery life. The general formula for converting tribasic lead sulfate to tetra basic lead sulfate is set forth below:
A common problem with traditional battery paste compositions and methods for curing is that the chemical characteristics of the resultant plates are not uniform, varying in quality. Other common problems include difficulty in the repeatability of production, uncertain and/or lengthy curing time, the large number of curing chambers needed to process plates, and high capital and energy costs.
Consequently, a need exists for improvements in battery pastes which may be used with conventional paste mixing and curing processes, procedures and equipment to produce positive and/or negative battery plates having greater uniformity, more consistent quality, more consistent reproducibility, requiring shorter and more consistent curing times, requiring less curing chambers to process the plates and less capital and energy costs than traditional positive and/or negative battery plate pastes and methods of paste mixing and curing.
The present invention overcomes the disadvantages and/or shortcomings of known prior art battery pastes and curing methods for battery plates and provides a significant improvement thereover.
A battery paste additive comprising micronized crystals of tetra basic lead sulfate and a method of producing the battery paste additive and battery plates is disclosed herein. The battery paste additive is added to a battery paste to promote and increase formation of tetra basic lead sulfate (TTBLS) crystals during paste mixing and curing. The battery paste additive may be used with conventional paste mixes and paste mixing and curing procedures and equipment to improve battery plate production and the resulting battery plates.
Accordingly, an object of the invention is to provide a battery paste additive comprising micronized tetra basic lead sulfate crystals.
Another object of the invention is to provide a battery paste additive that will reduce the time to cure the paste into the battery plate.
Yet another object of the invention is to provide a battery paste additive that may be used with conventional paste mixes and conventional mixing and curing procedures and equipment.
Yet another object of the invention is to provide a battery paste additive that improves the mechanical and physical strength of the resulting battery plate.
Yet another object of the invention is to create battery plates which are uniform in physical structure and quality.
Yet another object of the invention is to provide a battery paste additive allowing battery pastes and plates to be consistently reproducible.
Yet another object of the invention is to provide a battery paste additive which is used in battery pastes to produce plates that are cured in a reasonably consistent duration of time.
Yet another object of the invention is to provide a battery paste additive that may be used to produce positive battery plates.
Yet another object of the invention is to provide a battery paste additive which may be used to produce negative battery plates.
Yet another object of the invention is to provide a battery paste additive that reduces curing costs and capital costs associated with conventional curing procedures and curing chambers.
Numerous other objects, features and advantages of the present invention will become readily apparent from the detailed description and from the claims which follow.
While the invention is susceptible of embodiment in many different forms, there will be described herein in detail, preferred and alternate embodiments of the present invention. It should be understood however, that the present disclosure is to be considered an exemplification of the principles of the invention and is not intended to limit the spirit and scope of the invention and/or claims of the embodiments illustrated.
As disclosed herein, a battery paste additive is made and is then added to battery paste to improve the processing and the performance of battery plates. The battery paste additive comprises micronized tetra basic lead sulfate seed crystals, preferably with a median particle size from approximately 0.5 to 5.0 microns (preferably approximately one micron). These seed crystals are produced by a slow method of sulfuric acid addition to lead oxide, preferably in the form of HT-100 lead monoxide (99% or greater orthorhombic lead oxide raw material which is produced in a high temperature barton reactor followed by particle segregation via air classification, and due to its high reactivity, reacts with sulfuric acid and forms predominantly TTBLS crystals, resulting in a high percentage of TTBLS) and water to form TTBLS crystals which are subsequently centrifuged, dried and micromilled to produce micronized TTBLS crystals. The resultant battery paste additive is added to the paste during mixing, at a dosing level of approximately 0.25% to 5.00% of the weight of lead oxide in the mix, to accelerate and increase formation of tetra basic lead sulfate from tribasic lead sulfate in a battery paste, before curing. The micronized small crystals of tetra basic lead sulfate act as seeds or nucleation sites for formation of more TTBLS during paste mixing. The seed crystals eliminate the need for energy of crystallization, accelerating the conversion of tribasic lead sulfate to TTBLS.
Preferably, the above-described production of tetra basic lead sulfate crystals and milling process is used to produce micronized tetra basic lead sulfate crystals. The milling process breaks individual crystals into smaller particles. The resultant fine material of micronized TTBLS seed crystals may be used as a battery paste additive for greater production of TTBLS in the paste, as described in more detail below. Preferably, dry milling, without requiring the use of a grinding medium such as sand, is used to micronize the TTBLS crystals formed from the mixtures above. A hopper may be used to store and/or transfer the TTBLS product to the micromill. While a dry micromill process is described herein, any other methods known in the art for producing and/or separating fine particles of TTBLS may be used to produce the battery paste additive, so long as the advantages and features of the present invention are realized.
In the preferred embodiment of the present invention, after a first batch of micronized TTBLS crystals is made, a second batch of micronized TTBLS crystals is made in the same manner, except that the micronized TTBLS crystals form the first batch are added as a component in the second batch. The micronized TTBLS crystals initially produced by the above-described procedure (first batch) is then used as a component of a subsequent mixture. As described below, the subsequent mixture is the same mixture as the initial mixture, with the addition of micronized TTBLS crystals. Use of the initial micronized seed crystals from the first batch in the subsequent mixture (second batch) to produce the micronized TTBLS seed crystal additive performs essentially the same function that the micronized TTBLS seed crystal additive provides in the paste, promoting formation of TTBLS, and results in higher and more consistent purity of the TTBLS crystals produced. The resultant product of the subsequent mixture (second batch) may then be used as a battery paste additive. In an alternative embodiment, the initial mixture alone, without making the subsequent mixture, may be used as a battery paste additive.
Initial Mixture: In general, the production of the micronized tetra basic lead sulfate crystal additive uses an initial mixture of 1–90% (preferably approximately 75%), by total formula weight water, at a temperature between 0–100° C. (preferably between 50–100° C., and ideally approximately 90–100° C.); 10–70% (preferably approximately 15–20%) by total formula weight lead oxide; and 0.05–12% (preferably approximately 3–7%) by total formula weight dilute sulfuric acid (H2SO4) at a 1–99% concentration (preferably approximately at a 20–50% concentration, and ideally approximately at a 35% concentration). The sulfuric acid is added at two different times, as discussed below.
The initial mixture may be mixed in a reactor according to the following preferred procedure. The water is added to the reactor, mixing is begun, and the water is heated to the desired temperature, preferably approximately 90–100° C. The reactor water is then acidified with approximately 0.05–2.00%, preferably 0.05%, by total formula weight dilute sulfuric acid until the water is acidified at a pH of approximately equal or less than 2. The lead oxide is then added to the acidified water. Approximately 5–10%, preferably 5%, by total formula weight dilute sulfuric acid is then added to the mixture by a slow constant rate of sulfuric acid solution addition, as described below. Once sulfuric acid solution addition has completed, when the pH reaches approximately 9.5–8.5, the resultant initial mixture is centrifuged to remove excess water, the solid product is dried in a dryer, and then run through a hopper and a micromill to produce micronized TTBLS crystals. The resultant product is micronized TTBLS crystals. The dried sample may then be analyzed, and may also be analyzed prior to being run through the hopper and micromill.
Preferably, the micronized TTBLS product from the initial mixture or first batch above is then used in a subsequent mixture or second batch to produce the micronized TTBLS crystals paste additive. The subsequent mixture (second batch) and procedure is identical to the initial mixture, except for the addition of 0.01–5.00% by total formula weight, preferably 0.01%, micronized TTBLS from the initial mixture (first batch), preferably added after the addition of lead oxide and prior to the addition of sulfuric acid, to the mixture. The same procedure described for the initial mixture (first batch) is followed in the subsequent mixture (second batch). The dried, micromilled product of the subsequent mixture (second batch) may then be used as a battery paste additive. Use of the micronized crystal product form the initial mixture (first batch) in the subsequent mixture (second batch) promotes formation of TTBLS, resulting in a higher percentage of TTBLS crystals (or purity) and more consistent purity of the TTBLS crystals produced then the micronized TTBLS produced from the initial mixture. Alternatively, the micronized TTBLS product from the initial mixture may be used as the battery paste additive.
Sulfuric Acid Solution Addition: The following procedure is preferable for both the initial and subsequent mixtures described above. The initial weight of sulfuric acid and the weight of the sulfuric acid in the reactor is recorded and monitored at incremental periods of time, preferably every half hour. With the temperature at approximately 90–100° C., sulfuric acid solution addition using approximately 35% sulfuric acid is commenced and proceeds at a constant rate for approximately 2.5–4 hours. The total amount of sulfuric acid used in the addition process is approximately 5% by total formula weight.
Preferably, the sulfuric acid is added to the water/lead-oxide mixture slowly, at a constant rate of approximately 30–40 lbs/hour, preferably 30 lbs/hour, with vigorous mixing such that the rate of sulfuric acid addition allows for the formation of tetra basic lead sulfate. This slow addition of dilute acid favors the formation of tetra basic lead sulfate due to the localized in-situ stoichiometry providing an excess of lead oxide (PbO) molecules. By providing an environment rich with excess lead oxide molecules and dispersing the sulfuric acid rapidly due to vigorous mixing, a limited number sulfuric acid molecules favor formation of tetra basic lead sulfate, with each sulfuric acid molecule bonding with five (5) PbO molecules, as shown in the chemical reactions below. An addition rate of sulfuric acid which is too rapid may result in the formation of tribasic lead sulfate rather than tetra basic lead sulfate, as illustrated below.
After approximately two hours of sulfuric acid addition, the temperature, pH and weight of the sulfuric acid are monitored. The pH should preferably be approximately 10–11. After approximately 2.5 hours of sulfuric acid addition, the reactor batch may be sampled every fifteen minutes to check the pH. The sulfuric acid addition is preferably stopped when the pH is approximately 8.5–9.5. The resultant TTBLS crystal product may be sampled and analyzed for properties including the amount of lead, pH and X-ray diffraction (XRD) analysis to measure the amount of lead sulfate and lead oxide in the sample. The product is then centrifuged, dried in drying pans and in a drier and analyzed for properties including particle size and humidity. Larger particles may be micromilled again to produce TTBLS crystals of the desired size.
The reaction of lead oxide (PbO) with sulfuric acid (H2SO4) is exothermic and it is preferable to avoid boiling temperatures, such as those exceeding approximately 99–101° C. as foaming and batch overflow may result. If the temperature exceeds approximately 99–101° C., cool water may be applied until the temperature drops to below approximately 95–99° C.
Preferably, the resultant dried TTBLS micronized seed crystals will have a lead content of approximately 90.5–93.3% lead oxide by weight and a TTBLS content of approximately 90% or more TTBLS by weight. The lead content of the product may be measured by EDTA titration and may be used to determine that the proper ratio of sulfuric acid has been added. The TTBLS content may be measured by x-ray diffraction and may be used to determine the purity of the product. The resultant TTBLS product will also preferably have approximately 1.0% wt/wt or less moisture/humidity by weight, and a median particle size of approximately 0.5–5.0 microns, preferably one micron or less, and an appearance in color of tan yellow. TTBLS may discolor or blacken when exposed to ultraviolet light. It is therefore preferable to avoid extended exposure to UV light including sun and indoor lighting.
Although, a particular form of lead oxide, HT-100, which is high in orthorombic lead oxide, is preferred to produce the micronized seed crystals, any form of lead monoxide may be used. The resultant battery paste additive, when added to battery paste produces plates and batteries which have an increased battery life and performance, improved plate strength, and the processes for producing the additive and incorporating it into a battery paste are easily reproducible.
Although the addition of sulfuric acid to the initial and subsequent mixtures is preferably at a slow constant rate, such as that described above, other methods of sulfuric acid addition are foreseen, such as additions of sulfuric acid in multiple intervals, a slower rate of addition with less dilute sulfuric acid and/or a faster rate of addition with more dilute sulfuric acid. In addition, a continuous process in which sulfuric acid and lead oxide are combined into a continuous unbroken stream, eliminating the need for batch processing.
Although the procedure for micronizing the TTBLS crystals preferably requires centrifugation, drying, a hopper and a micromill, other methods of micronizing the TTBLS product are foreseen, such as crystal growth modification, sheer pumps, homogenization mills, cryogenic grinding and/or air classification. The use of other chemicals such as sodium sulfate is not required to produce a small particle size for the paste additive.
The resultant micronized TTBLS may be used as a battery paste additive by mixing approximately 0.25–5.00%, preferably approximately 1.0%, by weight of the lead oxide in the paste mix of the micronized TTBLS additive with conventional paste mixes using conventional paste mixers, pasting machines, tunnel dryers and curing chambers under standard conditions using standard manufacturing mixing and curing procedures.
Use of Micronized TTBLS Additive in Paste Mixing and Curing
Preferably, the amount of micronized TTBLS crystals added to the paste mix is approximately equal to 1.0% by weight of the lead oxide in the paste mix. An amount of micronized TTBLS crystals approximately equal to 1.0% by weight of the lead oxide in the paste mix is sufficient for use in both positive and negative plate paste mixes. The micronized TTBLS additive promotes and increases the formation of more TTBLS in the paste. TTBLS formation occurs during mixing, pasting and/or curing. The reaction conditions determine the rate of formation of TTBLS during each of the mixing, pasting and curing stages. The rate of formation is dependent on factors such as the temperature and time to prepare the paste mix.
Conventional paste mixing generally occurs at a temperature of approximately 45–65° C. In conventional paste mixes, TTBLS generally is not formed because this temperature is too low. The present invention allows formation of TTBLS in the paste during paste mixing at these low temperatures, as low as approximately 50° C. Due to the paste additive, a substantial amount of TTBLS will be formed during the paste mixing even at a low temperature, reducing or eliminating the need for TTBLS formation during the curing process.
In conventional paste mixes, at temperatures lower than 60° C., additional formation is necessary during the curing process. Generally, tetra basic lead sulfate will also be formed at temperatures lower than approximately 60° C. and can take place at approximately 40° C. However, at lower temperatures the rate of formation is reduced and the amount in the finished paste is also reduced. This can be offset by increasing the mixing time. This, however, increases the time to produce a paste mix beyond the 20–30 minute range preferred by the battery industry.
In conventional curing, temperatures of approximately 70–80° C. are required for formation of TTBLS. The present invention permits temperatures as low as 50° C. to be used during curing. The present invention may also be used at higher temperatures, resulting in more rapid formation of TTBLS than in conventional pastes. Preferably, the battery pastes containing the TTBLS additive are cured at a temperature approximately equal to or less than 50° C.
Plates made from pastes containing the additive may be stacked or separated, but are not required to be separated, during the curing process. The use of a polymer to bind TTBLS crystals in the paste is not required.
The preferred embodiment of the invention may be used in a variety of battery applications, including but not limited to automotive and industrial battery plate production. The preferred embodiment of the present invention may be used with positive or negative battery pastes for production of either positive or negative battery plates.
The additive produces more TTBLS in the paste, speeds up conversion of TRBLS to TTBLS and improves plate to plate reproducibility. As a result of the decreased curing time required due to the additive, fewer curing chambers are required to meet battery plate production requirements.
The paste density is a measure of the composition of the paste and also of its suitability for being pasted by commercial paste mixing machines for the positive or negative plate paste mix. Paste density is determined by measuring the weight of paste required to fill a cup having constant volume of 50 cubic centimeters. The “flock” component in
Battery paste mixes of the type described in
The data in
As can be seen in
In summary, as can be seen from the foregoing tests of the amounts of TTBLS and free lead oxide present in the battery paste mix at timed intervals during the mixing and curing process, the present invention produces highly favorable results, while at the same time overcoming the disadvantages and/or shortcomings of known battery paste materials. Such results are an improvement over known prior art battery pastes and battery paste materials, as well as the methods for producing the same.
The foregoing specification describes only the preferred embodiment and alternate embodiments of the invention. Other embodiments besides the above may be articulated as well. The terms and expressions therefore serve only to describe the invention by example only and not to limit the invention. It is expected that others will perceive differences, which while differing from the foregoing, do not depart from the spirit and scope of the invention herein described and claimed.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US3765943||Dec 9, 1970||Oct 16, 1973||Bell Telephone Labor Inc||Fabrication of lead-acid batteries|
|US3881954||Mar 18, 1974||May 6, 1975||Westinghouse Electric Corp||Method of producing a lead dioxide battery plate|
|US3973991||Mar 5, 1975||Aug 10, 1976||Nl Industries, Inc.||Light-weight lead-acid battery with laminated electrodes|
|US4331516||Dec 3, 1980||May 25, 1982||Eltra Corporation||Curing of tetrabasic lead pasted battery electrodes|
|US4336236||Mar 25, 1981||Jun 22, 1982||Nl Industries, Inc.||Double precipitation reaction for the formation of high purity basic lead carbonate and high purity normal lead carbonate|
|US4338163||Dec 3, 1980||Jul 6, 1982||Eltra Corporation||Curing of tetrabasic lead pasted battery electrodes|
|US4381250||Feb 2, 1982||Apr 26, 1983||Allied Corporation||Curing of tetrabasic lead pasted battery electrodes|
|US4401730||Sep 22, 1981||Aug 30, 1983||Gnb Batteries Inc.||Sealed deep cycle lead acid battery|
|US4415410||Feb 28, 1983||Nov 15, 1983||Allied Corporation||Forming of tetrabasic lead sulfate battery electrodes|
|US4507372||Apr 25, 1983||Mar 26, 1985||California Institute Of Technology||Positive battery plate|
|US4713304||Jun 18, 1986||Dec 15, 1987||Gnb Incorporated||Method of preparing lead-acid battery plates and lead-acid batteries containing plates so prepared|
|US4735870||Apr 25, 1986||Apr 5, 1988||California Institute Of Technology||Lead-acid battery construction|
|US4758372||Jun 16, 1986||Jul 19, 1988||Hubert Eirich||Method of producing lead paste for batteries|
|US4889778||Apr 25, 1988||Dec 26, 1989||C & D Power Systems, Inc.||Alkali metal polysilica gel electrolyte lead-acid battery and method for making the same|
|US4982482||Feb 24, 1989||Jan 8, 1991||Caltec International, Inc.||Method for the manufacture of lead-acid batteries and an associated apparatus and associated lead-acid battery|
|US4986317||Jun 16, 1988||Jan 22, 1991||Matsushita Electric Industrial Co., Ltd.||Method for making electrode plate for lead storage batteries|
|US4996340||Nov 8, 1989||Feb 26, 1991||Ethyl Corporation||Intramolecular migration reactions|
|US5017446||Oct 24, 1989||May 21, 1991||Globe-Union Inc.||Electrodes containing conductive metal oxides|
|US5044067||Sep 12, 1990||Sep 3, 1991||Caltec International, Inc.||Method for the manufacture of lead acid batteries and an associated apparatus and associated lead-acid battery|
|US5045170||May 2, 1989||Sep 3, 1991||Globe-Union, Inc.||Electrodies containing a conductive metal oxide|
|US5079111||Jun 8, 1990||Jan 7, 1992||Caltec International, Inc.||Method for the manufacture of lead-acid batteries and an associated apparatus and associated lead-acid battery|
|US5096611||May 25, 1989||Mar 17, 1992||Globe-Union Inc.||Process for the production of battery paste|
|US5149606||Mar 12, 1991||Sep 22, 1992||Globe-Union Inc.||Method of treating a battery electrode with persulfate|
|US5252105||Oct 6, 1992||Oct 12, 1993||General Motors Corporation||Method of forming lead-acid battery electrode|
|US5273554||Mar 31, 1993||Dec 28, 1993||At&T Bell Laboratories||Process for fabricating a battery|
|US5276960||Mar 15, 1991||Jan 11, 1994||Caltec International, Inc.||Method for the manufacture of lead-acid batteries and an associated apparatus and associated lead-acid battery|
|US5290359||Dec 6, 1991||Mar 1, 1994||Globe-Union Inc.||Apparatus for production of a battery paste|
|US5302476||Dec 3, 1990||Apr 12, 1994||Globe-Union Inc.||High performance positive electrode for a lead-acid battery|
|US5314766||Oct 19, 1992||May 24, 1994||General Motors Corporation||Lead-acid battery electrode and method of manufacture|
|US5384217||Jul 6, 1992||Jan 24, 1995||Globe-Union Inc.||Battery plates having rounded lower corners|
|US5434025||Oct 29, 1993||Jul 18, 1995||Gnb Battery Technologies Inc.||Battery grids and plates and lead-acid batteries made using such grids and plates|
|US5460730||Jun 27, 1994||Oct 24, 1995||Varta Batterie Aktiengesellschaft||Process and apparatus for treating wastewater from lead battery production|
|US5540127||Jun 27, 1994||Jul 30, 1996||Globe-Union, Inc.||Process and apparatus for forming battery plates|
|US5601945||Jun 6, 1995||Feb 11, 1997||Ensci Inc.||Battery element containing porous substrates|
|US5652074||Jan 11, 1996||Jul 29, 1997||Gnb Technologies, Inc.||Battery grids, a method for making such battery grids and lead-acid batteries using such battery grids|
|US5660600||Mar 24, 1995||Aug 26, 1997||Lucent Technologies Inc.||Batteries and materials useful therein|
|US5690718||Oct 6, 1995||Nov 25, 1997||Global Aener/Cology Corp.||Battery paste recycling process|
|US5691087||Jul 1, 1996||Nov 25, 1997||Gnb Technologies, Inc.||Sealed lead-acid cells and batteries|
|US5759716||Jul 2, 1996||Jun 2, 1998||Ensci Inc||Battery element containing metal inhibiting additives|
|US5874186||Jun 11, 1997||Feb 23, 1999||Gnb Technologies, Inc.||Lead-acid cells and batteries|
|US5895732||Jul 2, 1996||Apr 20, 1999||Ensci, Inc.||Battery element containing macroporous additives|
|US5945236||Aug 10, 1998||Aug 31, 1999||Willis; John||Lead-acid battery electrolyte fluid solution additive|
|US5948566||Sep 4, 1997||Sep 7, 1999||Gnb Technologies, Inc.||Method for making lead-acid grids and cells and batteries using such grids|
|US5948567||Jan 9, 1998||Sep 7, 1999||Geo Specialty Chemicals, Inc.||Battery paste dispersant|
|US6117196||Dec 24, 1997||Sep 12, 2000||Bolder Technologies Corporation||Method of manufacturing a lead acid cell paste and battery|
|US6180286||Sep 16, 1998||Jan 30, 2001||Gnb Technologies, Inc.||Lead-acid cells and batteries|
|US6228527||Mar 2, 1999||May 8, 2001||The United States Of America As Represented By The Secretary Of The Navy||Magnesium solution phase catholyte seawater electrochemical system|
|US6395431||Oct 28, 1998||May 28, 2002||Valence Technology, Inc.||Electrolytes having improved stability comprising an N,N-dialkylamide additive|
|US6454977||Mar 6, 2000||Sep 24, 2002||Delphi Technologies, Inc.||Process for making battery plate|
|US6528211||Apr 24, 2000||Mar 4, 2003||Showa Denko K.K.||Carbon fiber material and electrode materials for batteries|
|US6531248||Sep 28, 2000||Mar 11, 2003||Squannacook Technologies Llc||Battery paste|
|US6555026||Nov 6, 2000||Apr 29, 2003||Valence Technology, Inc.||Stabilized electrochemical cell active material|
|US6617071||May 24, 2001||Sep 9, 2003||Delphi Technologies, Inc.||Active material for high power and high energy lead acid batteries and method of manufacture|
|US6623892||Jun 16, 2000||Sep 23, 2003||Sony Corporation||Nonaqueous electrolyte battery|
|US6632573||Feb 20, 2001||Oct 14, 2003||Polyplus Battery Company||Electrolytes with strong oxidizing additives for lithium/sulfur batteries|
|US6635192||Mar 8, 1999||Oct 21, 2003||Wolfgang Schwarz||Electrically conductive microcapillary composite matrix and method for producing same|
|US6635387||Mar 19, 2001||Oct 21, 2003||Johan C. Fitter||Method and apparatus for achieving prolonged battery life|
|US6733547||Dec 10, 2001||May 11, 2004||Delphi Technologies, Inc.||Method of making a paste composition for lead acid battery|
|US6749950||Mar 28, 2002||Jun 15, 2004||Delphi Technologies, Inc.||Expanded grid|
|US6755874||Jan 11, 2001||Jun 29, 2004||Delphi Technologies, Inc.||Plate making process for lead acid battery|
|US20020124388||Jan 11, 2001||Sep 12, 2002||Rongrong Chen||Plate making process for lead acid battery|
|US20030044683||Sep 30, 2002||Mar 6, 2003||Squannacook Technologies Llc, A Delaware Corporation||Battery paste|
|US20030106205||Dec 10, 2001||Jun 12, 2003||Daxing Ma||Paste composition for lead acid battery|
|US20030157405||Feb 21, 2002||Aug 21, 2003||Rongrong Chen||Electrode|
|US20030165742||Mar 4, 2002||Sep 4, 2003||Mann Gamdur Singh||Electrode|
|US20030175203||Feb 2, 2002||Sep 18, 2003||Werner Nitsche||Curing of positive plates|
|US20040121233||Apr 3, 2003||Jun 24, 2004||Penarroya Oxide Gmbh||Additive for producing a positive active material for lead-acid storage batteries, a method for its production and a method for its use|
|US20040234852||Dec 23, 2003||Nov 25, 2004||Penox Gmbh||Additive for producing the positive active material for lead-acid storage batteries, a method for its production, and its use|
|US20050048372||Sep 17, 2004||Mar 3, 2005||Delphi Technologies, Inc.||Electrode|
|US20050207969||Mar 19, 2004||Sep 22, 2005||Ges Technologies, S. De R.L. De C.V.||Production of tetrabasic lead sulfate from solid state reactions for the preparation of active plates to be used in lead-acid batteries|
|USRE36734||Jan 23, 1997||Jun 13, 2000||Johnson Controls Technology Company||Battery plates having rounded lower corners|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US8637183||Sep 2, 2008||Jan 28, 2014||Hammond Group, Inc.||Expanders for lead-acid batteries|
|US8808914||Feb 14, 2013||Aug 19, 2014||Energy Power Systems, LLC||Lead-acid battery design having versatile form factor|
|US9263721||Sep 25, 2012||Feb 16, 2016||Energy Power Systems LLC||Lead-acid battery design having versatile form factor|
|US20060093912 *||Sep 23, 2005||May 4, 2006||Mayer George E||Paste curing additive|
|US20080305396 *||Jun 6, 2007||Dec 11, 2008||David Paul Boden||Lead-acid battery expanders with improved life at high temperatures|
|US20090325068 *||Sep 2, 2008||Dec 31, 2009||David Paul Boden||Expanders for lead-acid batteries|
|US20100075231 *||Sep 25, 2008||Mar 25, 2010||Ut-Battelle, Llc||Lead Acid Battery Slurry Comprising Polyelectrolyte Comb Copolymers|
|US20140050986 *||Feb 15, 2013||Feb 20, 2014||Energy Power Systems, LLC||Active materials for lead acid battery|
|WO2008153977A1 *||Jun 6, 2008||Dec 18, 2008||Hammond Group, Inc.||Lead-acid battery expanders with improved life at high temperatures|
|WO2010027451A1||Sep 2, 2009||Mar 11, 2010||Hammond Group, Inc.||Improved expanders for lead-acid batteries|
|U.S. Classification||429/227, 429/228, 423/559, 29/2|
|International Classification||H01M4/58, C01G21/20, H01M4/56, H01M4/20, H01M4/14, H01M4/16, H01M10/06|
|Cooperative Classification||Y02P70/54, H01M4/56, Y02E60/126, H01M10/06, H01M4/14, Y10T29/10, H01M4/20, H01M4/16|
|European Classification||H01M4/16, H01M4/56, H01M4/20, H01M10/06, H01M4/14|
|Mar 23, 2004||AS||Assignment|
Owner name: HAMMOND GROUP, INC., INDIANA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BODEN, DAVID;LABOVITZ, BENJAMIN;REEL/FRAME:015131/0760
Effective date: 20040318
|May 17, 2010||REMI||Maintenance fee reminder mailed|
|Oct 5, 2010||SULP||Surcharge for late payment|
|Oct 5, 2010||FPAY||Fee payment|
Year of fee payment: 4
|May 23, 2014||REMI||Maintenance fee reminder mailed|
|Oct 10, 2014||SULP||Surcharge for late payment|
Year of fee payment: 7
|Oct 10, 2014||FPAY||Fee payment|
Year of fee payment: 8